1. Field of the Invention
This invention relates to a thread guide threading apparatus for threading a thread guide of a needle bar provided in a lower portion of a sewing head and a sewing machine provided with the thread guide threading apparatus.
2. Description of the Related Art
In conventional sewing machines, a needle bar is often provided with a thread guide guiding a thread extending from a needle thread take-up lever through a needle eye, along a needle bar. The thread guide needs to be threaded before the thread is passed through the eye of the needle supported on the lower end of the needle bar. In the conventional sewing machines, however, threading the thread guide is manually carried out by the user. On the other hand, the thread guide is often formed with a thread guard which is open only at one side in order that the thread may be prevented from easily disengaging from the thread guide during sewing.
In the preparation for sewing, however, the thread guide is sometimes close to the sewing head depending on a position of the needle bar stopped. In such a case, the needle bar needs to be located near an uppermost position in order that the thread may be passed through the needle eye, whether or not the sewing machine is provided with a threading apparatus. Accordingly, when the thread guide is threaded, a thread guide provided above the needle is located near the sewing head or the thread guide is located close to the sewing head when the needle bar is moved upward so that cloth is put into or taken out of a spaced defined between the needle and the sewing bed.
Under the foregoing condition where the thread guide is close to the sewing head, the operator has a difficulty in viewing the thread guide and it is difficult for the operator to thread the thread guide since a space between the thread guide and the sewing head is too narrow. Furthermore, even when the sewing machine is constructed so that the thread guide is automatically threaded after the sewing machine has been threaded, the thread guard of the thread guide is open only at one side in many cases, whereupon there is a possibility that the thread guide may not be threaded reliably.